Adjustable sight radius device for firearms



April 22, 1952 H. F. GANZHORN ADJUSTABLE SIGHT RADIUS DEVICE FOR FIREARMS Filed June 9. 1950 Patented Apr. 22, 1952 ADJUSTABLE SIGHT RADIUS DEVICE FOR FIREARMS Henry F. Ganzhorn, Washington, Ill.

Application June 9, 1950, Serial No. 167,080

1 Claim. 1

This invention relates to gun sights, and more particularly to a device for selectively varying the sight radius of a gun.

An object of this invention is to provide a sighting device for attachment to a gun which permits the user to select any one of a plurality of sight radii.

Another object of this invention is to provide a sighting device for a gun which may be moved into and out of an extended position with respect to the forward end of a gun barrel for obtaining various sight radii of a length greater than the length of the gun barrel.

A further object of this invention is to provide a sighting device for attachment to a gun which is simple in structure and relatively cheap to manufacture.

The above and still further objects and advantages of this invention will become apparent upon consideration of the following detailed description of the invention when taken in conjunction with the accompanying drawings, wherein:

Figure 1 is a side elevational view of the adjustable sight radius device of the present invention shown supported on the forward end of a gun barrel;

Figure 2 is a top plan view of the adjustable sight radius device shown in Figure 1;

Figure 3 is a sectional view taken along the line 3--3 of Figure 1;

Figure 4 is a side elevational view of a modified form of the adjustable sight radius device of the present invention, shown supported on the forward end of a gun barrel; and

Figure 5 is a sectional view taken along the line 5-5 of Figure 4.

Referring now more particularly to the drawings, wherein like reference numerals have been used throughout the several views to designate like parts, there is shown the adjustable sight radius device of the present invention, generally designated by the reference numeral I0, supported on a gun barrel I I contiguous to the xed front sight I2 and spaced from the rear sight The adjustable sight radius device I includes an elongated base I which rests upon the forward end of the gun barrel II and is xedly secured longitudinally thereof. As clearly shown in Figure 3, the base I5 is cut away to form a channelway I8 having a longitudinally extending ared tongue I'I rising from the bottom thereof.

Positioned upon the base I5 and mounted on the latter for sliding movement longitudinally thereof into and out of an extended position with respect to the forward end of the gun barrel II is a slide I8. The slide is provided with a longitudinally extending slot I9 which is complementary to the flared tongue I1 Iand cooperates with the latter to form a dovetail joint for supporting the slide I8 for the sliding movement longitudinally of the base I5.

The extended end of the slide I8 is provided with a transversely extending slot 28 which slidably receives and supports a sight 2I of the globe or blade type, the base 22 of the sight 2| being dovetailed and complementary to the transversely extending slot 20. Accordingly, the sight 2I may be readily assembled or disassembled with the slide I8.

At. spaced intervals along the upper exposed face of the slide I8 there is provided a plurality of transversely extending lines, generally designated by the reference numeral 23, each of the lines being provided with numerical indicia for indicating the position of the slide I8 with respect to the base I5, the base being provided with a reference line indicated by the numeral 24. As clearly shown in Figure 1, a side of the slide I8 is provided with a plurality of detent recesses, generally indicated by the reference numeral 25, the detent recesses being spaced along the length of the slide in substantial alignment with the transversely extending lines 23.

Extending transversely through the base I5 and selectively engageable in the detent recesses 25 is a detent 26 which is illustrated as a set screw including a threaded shank 21. Accordingly, the slide I8 can be secured at selected positions in its path of sliding movement corresponding to any one of the transversely extending lines 23.

The slide I8 is further provided with a longitudinally extending slot 28 which extends from a point adjacent to and spaced inwardly from the transversely extending slot 20 toward a point adjacent to and spaced inwardly from the other end of the slide I8. As clearly shown in Figures 1 and 2, the slot 28 accommodates the upper end of the fixed front sight I2, so that the slide I8 can be moved longitudinally of the barrel without the fixed sight I2 interfering with the sliding movement. Accordingly, the adjustable sight radius device I0 can be successfully utilized with either a gun including a fixed gun sight or one which does not have the conventional gun sight.

In actual use, the distance between the rear sight I3 and the adjustable front sight 2I may be selectively varied by moving the slide I8 tn any one of its extended positions with respect to the forward end of the gun barrel II. It is to be noted that a sighting radius of a length somewhat greater than the length of the barrel I I may be obtained by this arrangement. In the event that it is desired to obtain a sighting radius somewhat shorter than the length of the gun barrel II, it is merely necessary to withdraw the slide I8 fromthe channel I6 and reinsert the slide into the channelway with the sight 2l overlying the gun barrel II. From the foregoing, it is readily apparent that a wide range of sighting radii may be obtained with speed and facility.

In Figures 4 and 5, there is shown a modified form of the sighting device of the present invention, in which the base I5 is detachably secured to the gun barrel II by means of a clamp 30 which is either xedly secured to the base I5 or formed integrally therewith. The clamp includes two arcuate arms 3I, 32 complementary to the gun barrel II, and having their free ends arranged in spaced confronting relation with respect to.each other, as indicated by the reference numeral 33. Extending transversely through the free ends of the arcuate arms 3l, 32 and threadedly engaging the latter is a set screw 34 for selectively urging the arms 3l', 32 of the clamp 30 into embracing engagement with the gun barrel II, to thereby detachably secure the adjustable sight radius device I0 to the gun barrel II. From the foregoing, it is apparent that the adjustable sight radius device of the present invention can be utilized with any one of a plurality of rifles having different sizes of bores, as well as any number of Shotguns and other rearms.

Numerous other modifications of the sighting device of the present invention can be made without departing from the spirit of the invention as set forth in the appended claim.

What I claim is:

The combination with a gun barrel having a front sight rising therefrom and a rear sight rising from the barrel rearwardly of the front sight, of a base mounted on the barrel between the front and rear sights, said base having a longitudinal slideway in its upper side, a slide confined in said slideway and adjustable therein longitudinally of the gun barrel, said slide having a forward portion extending forwardly from said base and formed with a longitudinal slot receiving the front gun barrel sight, another front sight on the forward end of the slide and located forwardly of the front sight of the gun barrel, detent means acting between said base and said slide for securing said slide in selected longitudinal adjustment relative to said base and the gun barrel, said forward portion of the slide being formed with a transverse slot in its upper side, and said other front sight having a portion slidably confined in said slot whereby said other front sight is transversely adjustable across said slide.

HENRY F. GANZHORN.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 416,554 Blankman Dec. 3, 1889 1,021,905 Steers Apr. 2, 1912 1,323,149 Blizard Nov. 25, 1919 1,480,048 Davis Jan. 8, 1924 '1,582,063 McIntosh Apr. 27, 1926 FOREIGN PATENTS Number Country Date 150,035 Germany Apr. 16, 1904 

